[Android] Switch to DeviceUtils versions of GetPid, TakeScreenshot, and GetIoStats.

build/android/pylib/screenshot.py

 # Copyright 2013 The Chromium Authors. All rights reserved.
 # Use of this source code is governed by a BSD-style license that can be
 # found in the LICENSE file.
 
 import os
+import signal
 import tempfile
 
 from pylib import cmd_helper
 
 # TODO(jbudorick) Remove once telemetry gets switched over.
 import pylib.android_commands
 import pylib.device.device_utils
 
 
 class VideoRecorder(object):
@@ skipping 10 matching lines @@
   """
   def __init__(self, device, megabits_per_second=4, size=None,
                rotate=False):
     # TODO(jbudorick) Remove once telemetry gets switched over.
     if isinstance(device, pylib.android_commands.AndroidCommands):
       device = pylib.device.device_utils.DeviceUtils(device)
     self._device = device
     self._device_file = (
         '%s/screen-recording.mp4' % device.GetExternalStoragePath())
     self._recorder = None
-    self._recorder_pids = None
     self._recorder_stdout = None
     self._is_started = False
 
     self._args = ['adb']
     if self._device.old_interface.GetDevice():
       self._args += ['-s', self._device.old_interface.GetDevice()]
     self._args += ['shell', 'screenrecord', '--verbose']
     self._args += ['--bit-rate', str(megabits_per_second * 1000 * 1000)]
     if size:
       self._args += ['--size', '%dx%d' % size]
     if rotate:
       self._args += ['--rotate']
     self._args += [self._device_file]
 
   def Start(self):
     """Start recording video."""
     self._recorder_stdout = tempfile.mkstemp()[1]
     self._recorder = cmd_helper.Popen(
         self._args, stdout=open(self._recorder_stdout, 'w'))
-    self._recorder_pids = self._device.old_interface.ExtractPid('screenrecord')
-    if not self._recorder_pids:
+    if not self._device.GetPids('screenrecord'):
       raise RuntimeError('Recording failed. Is your device running Android '
                          'KitKat or later?')
 
   def IsStarted(self):
     if not self._is_started:
       for line in open(self._recorder_stdout):
         self._is_started = line.startswith('Content area is ')
         if self._is_started:
           break
     return self._is_started
 
   def Stop(self):
     """Stop recording video."""
     os.remove(self._recorder_stdout)
     self._is_started = False
-    if not self._recorder or not self._recorder_pids:
+    if not self._recorder:
       return
-    self._device.RunShellCommand(
-        'kill -SIGINT ' + ' '.join(self._recorder_pids))
+    self._device.KillAll('screenrecord', signum=signal.SIGINT)
     self._recorder.wait()
 
-  def Pull(self, host_file):
+  def Pull(self, host_file=None):
     """Pull resulting video file from the device.
 
     Args:
       host_file: Path to the video file to store on the host.
+    Returns:
+      Output video file name on the host.
     """
     host_file_name = host_file or ('screen-recording-%s.mp4' %
                                    self._device.old_interface.GetTimestamp())
     host_file_name = os.path.abspath(host_file_name)
     self._device.old_interface.EnsureHostDirectory(host_file_name)
     self._device.PullFile(self._device_file, host_file_name)
     self._device.RunShellCommand('rm -f "%s"' % self._device_file)
+    return host_file_name